Apparatus for the adjustment of paper sheets

ABSTRACT

Apparatus for positioning sheets on a pile of a delivery table after their printing in a printing press. A continuous conveyer is provided for carrying successive sheets to the pile. A frame is mounted adjacent the pile and the conveyer and at least one perforated drum is located in the frame and adapted to be connected to a source of vacuum for braking the conveyed sheets. A front layer adapted to engage the edge of the conveyed sheets to position the sheets on the pile is also mounted on the frame. The apparatus includes drive means for synchronously rotating the drum and oscillating the front layer comprising a first shaft journaled in the frame and means connecting the shaft to the conveyer for rotating the shaft jointly with it. A pin extends axially from one end of the first shaft eccentric to its longitudinal axis and a forked member which is linked to the front layer surrounds the eccentric pin. The rotation of the pin causes the forked member and the front layer to oscillate. A second shaft extends freely through the perforated brake drums and is journaled in the frame. Means connecting the first and second shafts are provided so that the second shaft will rotate conjointly with the first. The second shaft is provided with disc means which engage the periphery of the drums whereby the drums are themselves rotated with respect to the second shaft.

United States Patent [191 J iruse [451 Oct. 22, 1974 APPARATUS FOR THE ADJUSTMENT OF PAPER SHEETS [75] Inventor: Jaroslav Jiruse, Blansko,

Czechoslovakia [73] 'Assignee: Adamovske Strojirny, narodni podnik, Adamov, Czechoslovakia [22] Filed: May 21, 1973 [21] Appl. No.1 362,486

[30] Foreign Application Priority Data Primary Examiner-Even C. Blunk Assistant Examiner-James W. Miller Attorney, Agent, or Firm-Murray Schaffer [571 ABS TRACT Apparatus for positioning sheets on a pile of a delivery table after their printing in a printing press. A continuous conveyer is provided for carrying successive sheets to the pile. A frame is mounted adjacent the pile and the conveyer and at least one perforated drum is located in the frame and adapted to be connected to a source of vacuum for braking the conveyed sheets. A front layer adapted to engage the edge of the conveyed sheets to position the sheets on the pile is also mounted on the frame. The apparatus includes drive means for synchronously rotating the drum and oscillating the front layer comprising a first shaft journaled in the frame and means connecting the shaft to the conveyer for rotating the shaft jointly with it. A pin extends axially from one end of the first shaft eccentric to its longitudinal axis and a forked member which is linked to the front layer surrounds the eccentric pin. The rotation of the pin causes the forked member and the front layer to oscillate. A second shaft extends freely through the perforated brake drums and is journaled in the frame. Means connect ing the first and second shafts are provided so that the second shaft will rotate conjointly with the first. The second shaft is provided with disc means which engage the periphery of the drums whereby the drums are themselves rotated with respect to the second shaft.

7 Claims, 4 Drawing Figures MTENTED DU 2 2 I974 3.843.116 sum ear 4 I APPARATUS FOR THE ADJUSTMENT OF PAPER SHEETS BACKGROUND OF INVENTION The present invention relates to apparatus for positioning sheets on a pile in a printing press and in particular to the drive mechanism by which the sheets may be braked and adjusted as they are delivered from a continuous conveyer.

Delivery devices by which paper sheets are successively conveyed from the press to a pile at the delivery table are in common use. Generally, the delivery device employs a. mechanism referred to as a front layer which isadapted to engage the edge of the moving sheet and adjustably position it on the pile. Sometimes a brake mechanism is employed in conjunction with the front layer so that the speed of the conveyed sheets may be sufficiently reduced to avoid damage to them.

it has been known to substitute oscillating front stops for the front layer particularly where the speed of the delivered sheets has been sufficiently reduced. The oscillating motion of the front stops is obtained from a drive mechanism which employs a plurality of cams and levers independently driven and actuated independently of the associated brake mechanism. This mechanism is generally reliable but has the disadvantage that its cams and lever construction is quite complicated and needs particular adjustment periodically during operation as well as being expensive in production.

Another known device works in such a manner that the transferred paper sheet is released by the grippers of the conveyer at a timed interval so that it continues to be conveyed to the front layers by the braking means itself. In this instance the braking means comprises drums having a perforated outer surface which is placed under a vacuum so that the paper sheets are sucked to it. In such a mechanism the brake drums are mounted in a housing which itself forms a fixed front layer member. The housing is adjustable according to the size of the paper sheets being conveyed. Front stops having an oscillating motion are employed instead of the moving front layer. The drive of such a mechanism is provided that rotary motion from the rotating parts of the printing machine itself are transferred to the braking drums by means of a chain, a drive belt or by a gear transmission. The oscillating motion of the front stops is derived independently from an eccentric or a cam actuated by a series of pull rods. A disadvantage of this mechanism is that the sheets tends to be thrown back into the direction of the delivery conveyer by the oscillating front stops. This results in an imperfect adjustment and positioning of the sheets on the pile. This is a particular problem when the sheets are delivered at extremely high working speeds.

Another known mechanism similar to the preceding one is sometimes employed. This similar mechanism is provided with fixed front stops and the final adjustment of the paper sheet on the pile is achieved by a front layer which is arranged in the plane of the braking drums. The drive of the front layer is derived from an eccentric mechanism which is mounted on a rotary shaft which simultaneously mounts the braking drums themselves. This mechanism has the disadvantage that the oscillating front layer has a working stroke derived from the rotation of the braking drums themselves which is too large to achieve the proper adjustment of the sheets on the pile. The largest stroke of. the front layer is at its end portion and no stroke movement is shown in the place of its oscillating axis. As a result the paper sheets are not perfectly positioned on the pile.

It is the object of the present invention to provide apparatus for positioning sheets on a pile in a printing press which overcomes the disadvantages and difficulties of the prior art devices.

It is a further object of the present invention to provide apparatus for positioning sheets on a pile employing a front layer and a braking mechanism in combination.

It is a further object of the present invention to provide apparatus for positioning paper sheets on a pile in a printing press in which the front layer and the brake mechanism are synchronously driven so that the rotation of the braking drums and the oscillation of the front layer are obtained in a predefined manner capable of their most efficient independent operation.

it is a further object of the present invention to provide a drive means for synchronously driving the braking drums of the brake mechanism and for oscillatingly moving the front layer mechanism.

It is a further object of the present invention to provide apparatus for mounting the brake mechanism and the front layer so as to be jointly adjustable to accommodate different sized paper sheets.

The above objects, other objects, and numerous advantages of the present invention will be seen from the foregoing disclosure.

SUMMARY OF INVENTION According to the present invention apparatus for positioning sheets on a pile of a delivery table after their printing in a printing press is provided comprising a continuous conveyor for carrying successive sheets to the pile, a frame mounted adjacent the pile and the conveyer, at least one perforated d'rum located in the frame and adapted to be connected to a source of vacuum for braking the conveyed sheets and a front layer adapted to engage the edge of the conveyed sheets to position the sheets on the pile. The apparatus includes drive means for synchronously rotating the drum and oscillating the front layer comprising a first shaft journaled in the frame and means connecting the shaft to the conveyer for rotating the shaft jointly with it. A pin extends axially from one end of the first shaft eccentric to its longitudinal axis and a forked member which is linked to the front layer surrounds the eccentric pin. The rotation of the pin causes the forked member and the front layer to oscillate. A second shaft extends freely through the perforated brake drums and is journaled in the frame. Means connecting the first and second shafts are provided so that the second shaft will rotate conjointly with the first. The second shaft is provided with disc means which engage the periphery of the drums whereby the drums are themselves rotated with respect to the second shaft.

An advantage of the present invention is seen from the above. According to the invention the front layer and the braking drums are rotated synchronously with each other via an interconnected drive system which while being driven directly from the same sheet conveyer provides a different rhythm and stroke of movement for the brake drums and the front layer.

Preferably the conveyer includes an endless chain drive and the means by which the conveyer and the first shaft are connected comprise a double drive gear including a first sprocket wheel meshing with the chain and a gear fixed with the sprocket wheel meshing with a second gear fixed to the first shaft. The first and second shafts are preferably parallel to each other and are interconnected by simple gear means. An advantage of this construction'lies in the fact of its simplicity and direct drive. A further advantage arising from the present invention lies in the fact that the front layer and the rotating drums can bemounted in a single frame which frame can be adjustably positioned on the side walls of the printing machine so that its working stroke along its entire length is the same relatively to'thepile of sheets and is sufficiently large so that it enables a reliable and perfect adjustment of the paper sheets on the pile no matter what the .size of the pile may be. I

Full details of the present invention are given in th following description and are shown in the attached drawings.

BRIEF DESCRIPTION OF DRAWINGS FIG. '1 is a schematic side view showing the conveyer,

. the delivery table, and the apparatus according to the DESCRIPTION OF INVENTION As seen in FIG. 1 the apparatus for delivering the paper sheets'to a pile, generally depicted by the letter P, comprises an endless chain conveyer generally depicted by the letter C including a drive chain 40 rotatable by a driven sprocket wheel 41 in the direction shown 'by the arrow, and as seen in FIG. 2 guided between a support bar 42 and a guide bar 43 fixed to the side walls of the printing machine. The conveyer may be perforated under suction or provided with gripper means by which the edge of the paper sheet is grasped, or any of the other conventional forms'of conveyer mechanisms. Mounted below the conveyer and adjacent to the pile is a braking and adjusting device generally depicted by the letter B, which contains the apparatus of the present invention. The pile itself may have a fixed bottom or an elevator bottom and may be provided with fixed stop means as is generally the case.

The braking and adjusting device according to the present invention comprises a sprocket wheel 1 which is fixedly connected to a gear 2 forming therewith a double driving wheel generally bearing the numeral 3 as seen in FIGS. 2 and 4. The double driving wheel 3 is rotatably mounted on a pivot pin 4 which is fixed on a channel or U-shaped beam frame member 5. The frame member 5 is mounted to be adjustably shiftable on guide bars 6 which are fixed to the parallel spaced walls of the printing machine.

As seen in FIG. 4 the frame 5 is provided with a pair of spaced bearing blocks 7 and 8 in which is rotatably mounted a shaft 9 extending parallel to the axle 4 of the double wheel 3. At this end the shaft 9 is provided with a fixed gear 10 which meshes with the gear 2 of the double wheel 3. At the opposite end of the shaft 9 a pin 11 extends axially but eccentrically offset from its longitudinal center. A radial bearing 12 is mounted about the pin 11 and a fork 13-surrounds the bearing. The stem of the fork 13 is fixed at its free end on a shaft 14 which is freely journaled in block holders l5 fixed on the lower surface of the frame 5. Because of the eccentric positioning of the pin 11 the rotation of the shaft 9 causes the fork 13 to take an elliptical path thus swinging the shaft 14 in a generally oscillating motion. The shaft 14 extends along the length of the frame 5 and has fixed at each of its ends an arm 16 which extends generally upwardly of the frame'S. Each of the free ends of the arms 16 pivotally carries a block 17 which is secured to the front layer 18. The front layer 18, as seen in FIG. 2 is aflat sheet-like member having a first portion extending parallel to the bottom of the frame 5 from the arm 16 to the front of the frame 5 from which it then is bent to angle downwardly so as to have a front portion which is generally vertical to the bottom of the pile. The front layer 18 extends substantially across the entire width of the frame 5 so as to be co-extensive with the pile and with the sheets to be deposited thereon. The front layer- 18 is also provided with cut out portions through which the brake mechanisms to be described later can'extend also in contact with the paper sheet. The forward portion of the front layer 18 is supported by a pair of pivotal blocks 19 which are secured to the undersurface of the layer 18. The blocks 19 are pivoted at one end of a substantially vertical lever 20 which lever is pivoted at its other end in a block 21 fixed toward the front end of the bottom surface of the frame 5. The arm 16 and the lever 20 and their pivotal connections 17 and 19 provide a quadrilateral linkage system'for the front layer 18 which on swinging of the shaft 14 causes the front portion of the layer 18 (i.e., that portion which engages the edge of the paper sheet deposited on the pile) to move in a working stroke which is the same relatively along its entire dimension so that the front layer 18 is moved from a position away from the pile to a position in which it engages the edges of the sheet of the pile which are parallel to each other as, seen by the dotted lines of FIG. 1. Thus, the front layer 18 rather than being pivoted in its movement is oscillatingly shifted parallel to its given position.

As seen in FIGS. 2 and 3 the shaft 9 has a drive gear 22 fixed to it which engages with a driven gear 23 which is fixed on a second shaft 24 which extends parallel to the first shaft 9. Toward each end of the shaft 24 there .are removably attached a carrier disc 25 which is provided with an axial neck. A pin 26 extends through the neck and through a diametrical slot 27 at the end of the shaft securing the two for conjoint rotation. Thecarrier discs 25 are axially secured on the shaft 24 by a spring-like securing element 29 which is removably fixed on a neck 28 formed at the end of the shaft 24. The carrier discs 25 are provided with radial slots 30 at their outer circumference which engage with a gear tooth 31 formed on the circumference of a cylindrical brake drum 32. The brake drums 32 are rotatably mounted about a brake body 34 which is fixed on the bottom wall of the frame 5. The brake drum 32 is provided with a plurality of suction openings 33 which communicates with an enlarged chamber 35 in the brake body 34 to which an inlet channel 37 is provided leading from a non-illustrated supply of vacuum or suction air. To the brake bodies 34 are fixed the outer race of the bearing 38, the inner race of which is mounted to the main shaft 24. In this manner the shaft 24 is rotatable freely within the body 34 and when so rotated can carry with it the brake drums 32. The brake drums protrude out of the cut outs 39 formed in the front layer 18. The cut outs 39 are of a greater width than the similar dimension of the brake drums so that the brake drums may be spaced axially apart from each other by adjustment of the retaining mechanism 28 and 29 to accommodate for varying widths of paper sheet.

The drive mechanism according to the present invention operates as follows:

The conveyer C is caused to carry successive sheets of paper from the printing press in the direction of the arrow so that the sheets pass successively over the braking and adjusting apparatus B to be deposited on the pile P. Simultaneously with the movement of the conveyer chain 40 the double drive gear 3 causes the rotation of the shaft 9. The rotary motion of the shaft 9 is transferred via the drive gear 22 and the driven gear 23 to the second shaft 24. The second shaft 24 causes the carrier discs 25 to rotate the braking drums 32 continuously at a rate selected by the relative sizes of the intermeshing gears and the speed of the conveyer chain 40. The braking drum 32 thus presents a continuously movable perforated surface through which suction is applied so that as the paper sheet is carried over the braking drums 30 the sheet may be caused to be arrested and braked in'its forward movement onto the pile P. The oscillating and shifting movement of the front layer 18 as described earlier is also derived from the same source, namely the rotation of the countershaft 9. The rotating countershaft 9 causes the eccentrically positioned pin 11 together with its bearing 12 in an elliptical path which gives a swinging movement to the fork 13. The fork 13 causes the shaft 14 to swing about its longitudinal central axis, thus swinging the arms 16. Since the arms 16 and the lever define with the top portion of the front layer 18 and the base of the frame 5 a quadrilateral pivotable lever system the front portion of the front layer 18 which is intended to engage the edge of the sheet 16 is moved reciprocatingly horizontally with respect to the bottom of the pile P so that it engages the edge of the sheets being deposited on the pile and moves them laterally into proper adjustments. The levers 20 have the function of thus ensuring the guiding of the front layer 18 in its proper parallel positions.

Thus, as seen from FIG. 1 as the conveyer 40 carries a sheet over the braking drums 35 the suction through the perforations 33, the chamber 35, the conduit 36 and the inlet 37 sufficiently grasp and slow down the moving paper so that it falls on the pile while simultaneously the front layer 18 lays the paper squarely on the pile.

As it sometimes happens the suction channels 35 and 36 and the supply tube sometime become clogged with dust and dirt and require cleaning periodically. This can be easily accomplished by simply removing the carrier disc from the second shaft 24 by pushing the pin 26 out from the slot 27. This simultaneously loosens the braking drum 32 from its engagement with the carrier disc 25 and it may be removed with the carrier disc. Access into the brake body 34 is provided via the cut outs 39 provided in the front layer 18.

Adjustment of the frame 5 which carries both the braking drums and the front layer 18 is accomplished by any conventional mechanism connecting the frame 5 with the guide bars 6 so that the frame can bemoved toward and away from the pile P in accordance with the size of the paper being utilized. An advantage of the apparatus according to the present invention lies in the fact that it enables adjustment of the brake and front layer simultaneously even during the printing operation of the machine. A further advantage is the fact that the adjustment for the size of the paper in no way interferes with either the rotation of the brake mechanism nor the reciprocating parallel movement of the front layer 18.

In accordance with the present invention the front layer mechanism itself is not pivoted but is caused to swing in parallel relationship between two apparently fixed positions so that the working stroke of the front layer is throughout its entire range of movement the same relatively to the pile of sheets and that this range of movement is sufficiently large no matter the height of the pile so that perfect adjustment of each of the succeeding paper sheets in the pile is accomplished. A further advantage is obtained in the synchronous connection between the rotation of the brake'drum and the front layer member so that each may be actuated at a relatively different rate. In particular the choice of the driven and drive gears between the shafts 9 and 24 can be chosen so as to provide a slower rotational speed for the braking drurnsrelative to the movement of the conveying apparatus itself so that the braking drum will be able to efficiently suck on the sheet and function as a brake of the forward speed.

Various modifications, changes and embodiments have been suggested. Others will be obvious to those skilled in this art. Accordingly, it is intended that the present disclosure be taken as illustrative of the invention and not as limiting thereof.

What is claimed is:

1. Apparatus for positioning sheets on a pile after printing in a printing press comprising a continuous conveyor for carrying successive sheets to said pile, a frame mounted adjacent said pile and said conveyor, at least one perforated drum located in said frame adapted to be connected to a source of vacuum for braking said conveyed sheets, a front layer adapted to engage the edge of said conveyed sheet and drive means for synchronously rotating said drum and oscillating said front layer to brake successive sheets and adjust their position on said pile comprising a first shaft journaled in said frame, means connecting said conveyor to rotate said first shaft jointly on movement of said conveyor, a pin extending axially from one end of said first shaft eccentric to the longitudinal axis thereof, a forked member linked to said-front layer surrounding said eccentric pin and oscillating on rotation thereof, a second shaft extending freely through said drums and journaled in said frame, means connecting said first and second shafts for conjoint rotation, bearing means for freely mounting said drum about said second shaft, means interconnecting said second shaft and the periphery of said drum for causing rotation of said drum conjointly with the rotation of said second shaft and a four bar linkage supporting said front layer, one of said bars being movable by said forked member enabling the reciprocation of said front layer in a parallel arrangement on movement of said forked member.

2. The apparatus according to claim 1 wherein said conveyer comprises an endless chain and said means for connecting said conveyer and said first shaft comprises a sprocket wheel meshing with said chain, a gear fixed to said sprocket wheel and a second gear fixed to said first shaft and meshing therewith.

3. The apparatus according to claim 1 wherein said first and second shafts are arranged parallel to each other and said first shaft includes a driving gear fixed to it and said second shaft includes a driven gear fixed to it meshing with said driving gear.

4. The apparatus according to claim 1 wherein said front layer is shiftably mounted on said frame and said frame is adjustably mounted on the support of said printing press whereby said front layer and rotatable drums are selectively positionable with respect to said pile.

5. The apparatus according to claim 1 wherein said front layer comprises a first horizontal portion and a second vertical portion and said four bar linkage comprises a first arm connected at one end of said horizontal portion and at the other end to the forked member and a second arm pivotally connected at one end to the forward part of the horizontal portion and at its other end to the frame.

6. The apparatus according to claim 1 wherein the means connecting said second shaft and said drum comprises a disc fixed about its center to said second shaft, said disc having a radial slot about its circumference, said perforating drum having a tooth extending from the periphery thereof into said slot whereby said disc and said perforated drum are interconnected.

7. The apparatus according to claim 6 including means for removably securing said disc in position along said second shaft. 

1. Apparatus for positioning sheets on a pile after printing in a printing press comprising a continuous conveyor for carrying successive sheets to said pile, a frame mounted adjacent said pile and said conveyor, at least one perforated drum located in said frame adapted to be connected to a source of vacuum for braking said conveyed sheets, a front layer adapted to engage the edge of said conveyed sheet and drive means for synchronously rotating said drum and oscillating said front layer to brake successive sheets and adjust their position on said pile comprising a first shaft journaled in said frame, means connecting said conveyor to rotate said first shaft jointly on movement of said conveyor, a pin extending axially from one end of said first shaft eccentric to the longitudinal axis thereof, a forked member linked to said front layer surrounding said eccentric pin and oscillating on rotation thereof, a second shaft extending freely through said drums and journaled in said frame, means connecting said first and second shafts for conjoint rotation, bearing means for freely mounting said drum about said second shaft, means interconnecting said second shaft and the periphery of said drum for causing rotation of said drum conjointly with the rotation of said second shaft and a four bar linkage supporting said front layer, one of said bars being movable by said forked member enabling the reciprocation of said front layer in a parallel arrangement on movement of said forked member.
 2. The apparatus according to claim 1 wherein said conveyer comprises an endless chain and said means for connecting said conveyer and said first shaft comprises a sprocket wheel meshing with said chain, a gear fixed to said sprocket wheel and a second gear fixed to said first shaft and meshing therewith.
 3. The apparatus according to claim 1 wherein said first and second shafts are arranged parallel to each other and said first shaft includes a driving gear fixed to it and said second shaft includes a driven gear fixed to it meshing with said driving gear.
 4. The apparatus according to claim 1 wherein said front layer is shiftably mounted on said frame and said frame is adjustably mounted on the support of said printing press whereby said front layer and rotatable drums are selectively positionable with respect to said pile.
 5. The apparatus according to claim 1 wherein said front layer comprises a first horizontal portion and a second vertical portion and said four bar linkage comprises a first arm connected at one end of said horizontal portion and at the other end to the forked member and a second arm pivotally connected at one end to the forward part of the horizontal portion and at its other end to the frame.
 6. The apparatus according to claim 1 wherein the means connecting said second shaft and said drum comprises a disc fixed about its center to said second shaft, said disc having a radial slot about its circumference, said perforating drum having a tooth extending from the peRiphery thereof into said slot whereby said disc and said perforated drum are interconnected.
 7. The apparatus according to claim 6 including means for removably securing said disc in position along said second shaft. 